There are quite a few, at least in the casual and PC game sector. You stand almost no chance on consoles, as the console manufacturers won't give you the SDKs and won't let you sell your game for their console unless you go through an established publisher. The publishers generally require you to sign over all "IP" (concept, names, characters, art, code) to them, which doesn't make it attractive to your average startup founders.

The only publisher I know of that doesn't do this is GameCock, (http://www.gamecockmedia.com/) they're effectively a startup as well, although the founders are industry veterans.